Image projection apparatus

1. An image projection apparatus to enlarge and project image data on a screen using light emitted from a lamp, the apparatus comprising: a housing having a top panel, a bottom panel, and plurality of side panels; a duct which includes a first absorption hole disposed in a first one of the side panels through which the air is absorbed, and a main exhaust hole disposed in a second one of the side panels through which the air is exhausted, connects elements that need to be cooled in series, and forms an air-flow path to cool the elements; and at least one fan to control air flow via the air duct, wherein the elements are arranged from the first absorption hole to the main exhaust hole according to an operating temperature of the elements and comprise a power supply unit to supply power, a lamp, and a ballast to operate the lamp, and the at least one fan comprises a first fan arranged between the power supply unit and the ballast and a second fan arranged between the ballast and the lamp.

2. The apparatus of claim 1 , wherein the elements are arranged from the first absorption hole to the main exhaust hole according to an operating temperature of the elements so that one of the elements having a lower operating temperature than the other one of the elements is disposed adjacent to the first absorption hole.

3. The apparatus of claim 1 , wherein the elements comprises an optical modulator which modulates light irradiated from the lamp to correspond to image data, and the duct further comprises a second absorption hole which communicates with the optical modulator.

4. The apparatus of claim 3 , wherein the at least one fan further comprises a third fan which controls the air to flow into the duct via the second absorption hole to cool the optical modulator.

5. The apparatus of claim 4 , wherein a cooling capacity of the second fan is larger than a cooling capacity of each of the first fan and the third fan.

6. The apparatus of claim 1 , further comprising: a vane placed at an outlet of the first fan to induce the air to flow to the ballast.

7. The apparatus of claim 1 , further comprising: an induction duct diverged from the duct at an outlet of the second fan to induce the air flow to a front part of the lamp.

8. The apparatus of claim 1 , further comprising: a light leakage prevention unit placed between the lamp and the main exhaust hole in the duct to prevent light irradiated from the tamp from leaking via the main exhaust hole.

9. The apparatus of claim 8 , wherein the light leakage prevention unit comprises a plurality of ribs which extend from an outlet of the lamp to the main exhaust hole and include at least one curvature portion to change an extension direction of the ribs so that the light is cut off.

10. The apparatus of claim 9 , wherein the light leakage prevention unit further comprises an uneven portion provided on the ribs and disposed adjacent to an end of the lamp to reflect the light toward the lamp.

11. The apparatus of claim 4 , wherein the duct comprises: a first duct which accommodates the power supply unit and includes the first and second absorption holes; a second duct which accommodates the ballast and communicates with the first duct; and a third duct which accommodates the lamp, includes the main exhaust hole, and communicates with the second duct.

12. The apparatus of claim 11 , wherein the first duct is a shield to prevent electromagnetic interference (EMI).

13. The apparatus of claim 11 , wherein the second duct comprises an absorption member installed on an inner wall thereof to absorb an operating noise of the ballast.

14. The apparatus of claim 11 , wherein the second fan is installed in the third duct, and the apparatus further comprising a dustproof member interposed between the second fan and the third duct to absorb vibration and noise generated from the second fan.

15. An image projection apparatus comprising a first and a second and a third ducts connected in series to form an air-flow path along which air flows within the first and second and third ducts; an absorption hole formed on the first duct; a main exhaust hole formed on the third duct; a lamp disposed in the third duct; a first and a second elements having a first and a second operating temperatures lower than a third operating temperature of the lamp and disposed in the first duct and the second ducts, respectively; and an optical system to receive light from the lamp, to modulate the received light according to image data, and to project the modulated light, wherein the first duct comprises a second absorption hole disposed adjacent to the optical system to cool the optical system.

16. The apparatus of claim 15 , wherein the optical system comprises an optical modulator to modulate the received light, and the air disposed adjacent to the modulator is absorbed into the first duct through the second absorption hole.

17. The apparatus of claim 16 , further comprising: a fan disposed adjacent to the second absorption hole of the first duct to absorb the air disposed around the optical modulator into the first duct.

18. The apparatus of claim 15 , wherein the air flows the first duct, the second duct, and the third duct along the air-flow path to cool the first and second elements and the lamp sequentially.

19. The apparatus of claim 15 , wherein the first element comprises a power supply unit, and the second element comprises a ballast.

20. The apparatus of claim 15 , further comprising: a first fan disposed to control the air to flow from the first duct into the second duct; and a second fan disposed in the passage to control the air to flow from the second duct into the third duct; and wherein a cooling capacity of the second fan is larger that that of the first fan.

21. The apparatus of claim 15 , further comprising: a dustproof member disposed between the second and third ducts.

22. The apparatus of claim 15 , wherein the third duct comprising an exhaust duct disposed between the lamp and the main exhaust hole to guide the air from the third duct to an outside thereof.

23. The apparatus of claim 22 , wherein the exhaust duct comprises two sub-ducts disposed adjacent to the main exhaust hole to guide the air toward the main exhaust hole in a direction different from the air path to prevent a leakage of light emitted from the lamp.

24. The apparatus of claim 22 , wherein the exhaust duct comprises an uneven portion to prevent a leakage of light emitted from the lamp through the main exhaust hole.

25. An image projection apparatus to enlarge and project image data on a screen using light emitted from a lamp, the apparatus comprising: a housing comprising a plurality of sides to house a plurality of elements; a duct which includes a first absorption hole through which the air is absorbed, and a main exhaust hole through which the air is exhausted, to connect elements that are cooled in series, and to form an air-flow path to cool the elements along lengths of two adjacent sides of the housing; and at least one fan to control air flow via the air duct, wherein the elements are arranged from the first absorption hole to the main exhaust hole according to an operating temperature of the elements and comprise a power supply unit to supply power, a lamp, and a ballast to operate the lamp, and the at least one fan comprises a first fan arranged between the power supply unit and the ballast and a second fan arranged between the ballast and the lamp.

26. A cooling apparatus used with an image projection apparatus comprising: a duct having an air-flow path and having an inlet and an outlet disposed at both ends of the air-flow path; a first element having a first operating temperature; a second element having a second operating temperature greater than the first operating temperature; a third element having a third operating temperature greater than the second operating temperature; and an optical system to receive light from the third element, to modulate the received light according to image data, and to project the modulated light, wherein the first, second, and third elements are disposed in the duct along the air-flow path from the inlet toward the outlet in order and the duct further comprises a second inlet disposed adjacent to the optical system to cool the optical system.

27. An image projection apparatus to enlarge and project image data on a screen using light emitted from a lamp, the apparatus comprising: a duct which includes a first absorption hole through which the air is absorbed, and a main exhaust hole through which the air is exhausted, to connect elements that are cooled in series, and to form an air-flow path to cool the elements, wherein the elements include a power source unit, a ballast, and a lamp in order; and at least one fan to control air flow via the air duct, wherein the elements are arranged from the first absorption hole to the main exhaust hole according to an operating temperature of the elements, the ballast operates the lamp, and the at least one fan comprises a first fan arranged between the power source unit and the ballast and a second fan arranged between the ballast and the lamp.